The leakage of noncombustible gas from refrigeration systems and the like has been determinable with the use of Halide gas leak detectors wherein there is a flame which distinctly changes color in the presence of Freon, Carrene and Methyl Bromide vapors. The concentration of these leaking gas vapors is low, for example 10%, with respect to the surrounding atmosphere; and the flame is produced by a clean burning gas such as Propane in the presence of a Halide reactor plate at or surrounding the flame. Heretofore, the shield or burner holder has not afforded sufficient obliteration against surrounding light, and for example it is next to impossible to detect leaks thereby in direct sunlight. In practice, there is a search hose leading to the burner holder, the terminal end of said hose being open and held near the potential leak points to be tested. Such a leak is referred to as a Perchlorethylene leak, Chloride being employed in the reaction plate, and is detected by color change in the Propane flame above the reactor plate; pale blue indicating no leakage present, pale green indicating slight leakage vapors present, brilliant green indicating moderate leakage vapors present, and brilliant peacock blue indicating heavy leakage vapors present. In bright sunlight the slight and moderate leaks are not detectable at all and even the most brilliant color change is not readily detectable. Therefore, it is a general object of this invention to provide a viewer that obscures the detection flame from all direct light that would normally interfere with the observation required by the technician in his search for leaks.
Heretofore, the shield or burner holder has been an open ended cylinder with a side window through which the changeable flame is observed; and all of this can remain unchanged with the present invention which provides a viewer that embraces the flame in the presence of the reactor plate, and all of which is obscured from direct light, especially sunlight when the detection process is carried on out of doors. With the present invention, there is a viewing tube intended to be used in a substantially horizontal disposition with the detection flame enclosed therein at one closed end, to be viewed from the other open end. A feature and object herein is to ventilate the aforesaid tube, not only to permit the heated products of combustion to escape, but also to permit a draft to proceed through the tube while the said open end thereof is substantially closed by the close proximity of the persons face when observing the said flame. The viewer is characterized by the baffled ventilators, one for the inlet by convection flow to the outlet of the gases heated by combustion during the process of observing the color of the detection flame obscured from surrounding light.
It is an object of this invention to protect the eye of a person viewing the flame exposed within the closed chamber, by a distance separation conducive to natural close-up observation, and by a ventilation system which operates inherently by means of convection.